Radionécrose cérébrale chez les patients irradiés pour cancer du nasopharynx: à propos de neuf cas

[Management of cerebral radionecrosis: experience in the Department of Neurology at the Mohammed V Military Teaching Hospital]

La radionécrose cérébrale est une complication rare mais redoutable de la radiothérapie externe pour les cancers ORL en particulier du nasopharynx et pour les tumeurs cérébrales. Peu de travaux se sont intéressés à cette complication aussi bien dans la population maghrébine qu'africaine. L'objectif de notre étude est donc de décrire les aspects démographiques, cliniques, paracliniques, thérapeutiques et évolutifs de la radionécrose cérébrale au sein du Service de Neurologie de l'Hôpital Militaire d'Instruction Mohammed V de Rabat (HMIMV) sur une durée de 18 ans (2000-2017). Il s'agissait de 04 femmes et 13 hommes âgés en moyenne de 50 ans. Le délai moyen entre la fin de la radiothérapie et le début des signes neurologiques était de 28 mois. La réalisation systématique d'une IRM cérébrale parfois complété d'une spectro-IRM avait permis de faire le diagnostic chez 100% des cas. Sur le plan étiologique, cette complication survenait après radiothérapie pour cancer du cavum et du larynx chez tous les cas. 15 patients ont été traités par l'association: corticothérapie en bolus, antiagrégants plaquettaires, associée à l'oxygénation hyperbare (OHB) avec une bonne évolution, et 2 patients, chez qui l'oxygénothérapie était contre-indiquée pour problème pulmonaire, et ORL, ont reçu l'association corticothérapie en bolus et antiagrégants plaquettaires avec une évolution stationnaire. À la lumière de ces résultats, nous insistons sur l'intérêt du diagnostic précoce en raison de la gravité potentielle de certains tableaux surtout neuropsychiatriques ainsi que sur le traitement par association bolus de corticoïdes + OHB car il est le meilleure garant d'une évolution favorable de ces atteintes, sans omettre le rôle crucial des mesures de prévention.

Late Toxicities after Conventional Radiotherapy for Nasopharyngeal Carcinoma: Incidence and Risk Factors

Background. To determine the incidence and analyze the factors affecting late toxicity for nasopharyngeal carcinoma patients treated with conventional radiotherapy. Patients and Methods. Retrospective analysis was performed on 239 NPC patients treated between 1993 and 2004 in our institution. One hundred and fifty-seven patients were treated with conventional fractionation (2 Gy per fraction, 5 fractions per week) and eighty-two patients with hyperfractionated radiotherapy (1.6 Gy per fraction twice a day, 5 days per week). One hundred fifty nine patients underwent neoadjuvant cisplatin based chemotherapy. Late toxicity was evaluated according to the RTOG/EORTC score. Results. Xerostomia was the most common related complication (98.7%). Neoadjuvant chemotherapy and hyperfractionated radiotherapy did not increase late toxicities. Multivariate analyses showed that radiation dose was a significant factor for hearing impairment, younger age for trismus, initial node status for neck fibrosis, and initial dental hygiene for dental complications. Female gender was associated with significantly higher incidence of trismus and hearing impairment. Conclusion. Conventional radiotherapy was associated with a high rate of late toxicities which affect patients’ quality of life. With the development of three-dimensional conformal radiotherapy and intensity modulated radiotherapy, a reduced incidence of radiation related complications could be expected.

Results of excision of cerebral radionecrosis: experience in patients treated with radiation therapy for nasopharyngeal carcinoma

OBJECT

In theory, the purpose of the treatment of cerebral radionecrosis (CRN), a nonneoplastic condition, is to minimize loss of brain function by preventing the progression and reversing some of the processes of CRN. In a practical sense, factors for achieving this purpose may include the following: removal of a CRN lesion that is causing mass effect, control of brain edema, prevention of recurrence of CRN lesions, minimization of adverse effects from treatments, and achievement of reasonably long and good-quality survivals. Based on these practical issues, the authors performed a retrospective study to evaluate the results of excision for the treatment of CRN.

METHODS

The authors retrospectively reviewed the results of excision of CRN lesions in a group of patients with temporal lobe CRN due to radiotherapy for nasopharyngeal carcinoma. Patients who had undergone surgery at the authors' institution between January 1998 and November 2008 were analyzed. Surgical results were evaluated by assessing postoperative resolution of brain edema, recurrence of temporal lobe CRN, surgery-related complications, and postoperative functional status and survival.

RESULTS

Twenty-four patients were included (age range 39-69 years; in 23 patients nasopharyngeal carcinoma was in remission). All patients underwent craniotomy for excision of the contrast-enhancing region. The indications for operation were temporal lobe CRN lesions with a mass-occupying effect beyond the temporal lobe. There were 32 craniotomies in all (mean postoperative follow-up 40 months). It was found that brain edema resolved rapidly postoperatively. The recurrence and reoperation rates were 6.3 and 3.1%, respectively. There were no surgery-related deaths. The median survival was 72 months, and 67% of the patients had a Karnofsky Performance Scale score of > or = 70% at the time of their last follow-up.

CONCLUSIONS

In a specific group of patients with CRN of the temporal lobe in whom the CRN lesions were causing a mass-occupying effect beyond the temporal lobe, excision of the contrast-enhancing region was safe and could achieve prompt resolution of brain edema and a low incidence of recurrence of CRN.

[Late neurotoxicity after nasopharyngeal carcinoma treatment]

PURPOSE

A retrospective analysis of risk factors for late neurological toxicity after nasopharyngeal carcinoma radiotherapy.

PATIENTS AND METHODS

Between 1993 and 2004, 239 patients with non metastatic nasopharyngeal carcinoma were treated by radiotherapy associated or not to chemotherapy. Radiotherapy was delivered with two modalities: hyperfractionated for 82 patients and conventional fractionation for 157 patients. We evaluated the impact of tumour stage, age, gender, radiotherapy schedule and chemotherapy on neurological toxicity.

RESULTS

After a mean follow-up of 107 months (35-176 months), 21 patients (8.8%) developed neurological complications, such as temporal necrosis in nine cases, brain stem necrosis in five cases, optics nerve atrophy in two cases and myelitis in one case. Five- and ten-year free of toxicity survival was 95 and 84% respectively. Young patients had greater risk of temporal necrosis, and hyperfractionated radiotherapy was associated with a significantly higher risk of neurological complications (14.6% vs 5.7%, p=0.02). On multivariate analysis, hyperfractionation and age were insignificant.

CONCLUSION

Late neurological toxicity after radiotherapy for nasopharyngeal carcinoma was rare. Younger age and hyperfractionation were considered as risk factors of neurological toxicity in our study.